Display device

ABSTRACT

A display device is provided. The display device of the present disclosure may include: a head including a display panel; an arm to which the head is pivotally coupled; a pole to which the arm is coupled; and a base to which the pole is coupled, wherein the base includes: a lower body forming a bottom; an upper body which is coupled to the lower body and to which the pole is fixed; a weight disposed between the lower body and the upper body; and a wheel disposed outside of the lower body, passing through the lower body and coupled to the weight.

CROSS-REFERENCE TO THE RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 18/132,136, filed on Apr. 7, 2023, which claims the benefit of earlier filing date and right of priority to Korean Patent Application No. 10-2022-0044095, filed on Apr. 8, 2022, the contents of which are all hereby incorporated by reference herein in their entirety.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present disclosure relates to a display device.

2. Description of the Related Art

With the development of the information society, there have been growing demands for various types of display devices, and in order to meet these demands, various display devices, such as a liquid crystal display (LCD), a plasma display panel (PDP), an electroluminescent display (ELD), a vacuum fluorescent display (VFD), an organic light emitting diode (OLED), etc., have been studied and used recently.

Among them, the LCD panel includes a TFT substrate and a color substrate which are positioned opposite each other with a liquid crystal layer interposed therebetween, and displays images by using light emitted from a backlight unit. Further, the OLED panel may display images by using a self light-emitting organic layer deposited on a substrate on which transparent electrodes are formed.

Recently, a structure for freely adjusting an angle or position of a display panel is actively researched.

SUMMARY OF THE INVENTION

It is an objective of the present disclosure to solve the above and other problems.

Another object of the present disclosure may be to provide a display device including a stand for a display panel.

Another object of the present disclosure may be to provide a structure for freely adjusting an angle or position of a head having a display panel.

Another object of the present disclosure may be to provide a structure for allowing various motions of a head, including a pivot motion, a tilt motion, a swivel motion, and an elevating motion, to be performed independently of each other.

Another object of the present disclosure may be to provide a structure for improving standing stability of a display device.

Another object of the present disclosure may be to provide a structure for improving driving stability of a moving base having a wheel.

In accordance with an aspect of the present disclosure, the above and other objectives can be accomplished by providing a display device including: a head including a display panel; an arm to which the head is pivotally coupled; a pole to which the arm is coupled; and a base to which the pole is coupled, wherein the base includes: a lower body forming a bottom; an upper body which is coupled to the lower body and to which the pole is fixed; a weight disposed between the lower body and the upper body; and a wheel disposed outside of the lower body, passing through the lower body and coupled to the weight.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and other advantages of the present disclosure will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIGS. 1 to 40 are diagrams illustrating examples of a display device according to embodiments of the present disclosure.

DETAILED DESCRIPTION

Description will now be given in detail according to exemplary embodiments disclosed herein, with reference to the accompanying drawings. For the sake of brief description with reference to the drawings, the same or equivalent components may be denoted by the same reference numbers, and description thereof will not be repeated.

In general, suffixes such as “module” and “unit” may be used to refer to elements or components. Use of such suffixes herein is merely intended to facilitate description of the specification, and the suffixes do not have any special meaning or function.

In the present disclosure, that which is well known to one of ordinary skill in the relevant art has generally been omitted for the sake of brevity. The accompanying drawings are used to assist in easy understanding of various technical features and it should be understood that the embodiments presented herein are not limited by the accompanying drawings. As such, the present disclosure should be construed to extend to any alterations, equivalents and substitutes in addition to those which are particularly set out in the accompanying drawings.

It will be understood that although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another.

It will be understood that when an element is referred to as being “connected with” another element, there may be intervening elements present. In contrast, it will be understood that when an element is referred to as being “directly connected with” another element, there are no intervening elements present.

A singular representation may include a plural representation unless context clearly indicates otherwise.

In the present application, it should be understood that the terms “comprises,” “includes,” “has,” etc. specify the presence of features, numbers, steps, operations, elements, components, or combinations thereof described in the specification, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, elements, components, or combinations thereof.

In the embodiments illustrated in the figures, representations of directions, such as up (U), down (D), left (Le), right (Ri), front (F), and rear (R) are merely for convenience of explanation, and are not intended to limit the technical features disclosed in this specification.

Referring to FIG. 1 , a display device 1 may include ahead 10. The head 10 may display images. The head 10 may be referred to as a display 10 or a display unit 10.

The head 10 may include a first long side LS1, a second long side LS2 opposite to the first long side LS1, a first short side SS1 adjacent to the first long side LS1 and the second long side LS2, and a second short side SS2 opposite to the first short side SS1. For convenience of explanation, it is illustrated and described that the first and second long sides LS1 and LS2 are longer than the first and second short sides SS1 and SS2, but it is also possible that lengths of the first and second long sides LS1 and LS2 may be approximately equal to lengths of the first and second short sides SS1 and SS2.

A direction parallel to the short sides SS1 and SS2 of the head 10 may be referred to as a first direction DR1 or an up-down direction. A direction parallel to the long sides LS1 and LS2 of the head 10 may be referred to as a second direction DR2 or a left-right direction. A direction perpendicular to the long sides LS1 and LS2 and the short sides SS1 and SS2 of the head 10 may be referred to as a third direction DR3 or a front-rear direction.

A side on which the head 10 displays an image may be referred to as a front side F, z, and a side opposite thereto may be referred to as a rear side R. The first short side SS1 may be referred to as a left side Le, x, and the second short side SS2 may be referred to as a right side Ri. The first long side LS1 may be referred to as an upper side U, y, and the second ling side LS2 may be referred to as a lower side D.

The first long side LS1, the second long side LS2, the first short side SS1, and the second short side SS2 may be referred to as edges of the head 10. Further, positions where the first long side LS1, the second long side LS2, the first short side SS1, and the second short side SS2 meet each other may be referred to as corners.

A position where the first short side SS1 and the first long side LS1 meet each other may be referred to as a first corner C1. A position where the first short side SS1 and the second long side LS2 meet each other may be referred to as a second corner C2. A position where the second short side SS2 and the second long side LS2 meet each other may be referred to as a third corner C2. A position where the second short side SS2 and the first long side LS1 meet each other may be referred to as a fourth corner C4.

Referring to FIGS. 1 and 2 , the display device 1 may include a base 20, a pole 30, and a motion module MM.

The base 20 may have a generally flat cylindrical shape. The base 20 may be placed on the ground.

The pole 30 may be elongated vertically. A lower end of the pole 30 may be coupled onto the base 20. The pole 30 may be adjacent to a circumference of an upper surface of the base 20. A handle 39 may be coupled to an upper end of the pole 30. The pole 30 and the aforementioned base 20 may be collectively referred to as a stand.

The motion module MM may extend in a direction crossing the pole 30. A first side of the motion module MM may be coupled to a rear side of the head 10. A second side of the motion module MM may be adjacent to the upper end of the pole 30 and may be coupled to the pole 30. An articulated connector 40 may be coupled to the rear side of the head 10, an elevating module 60 may be coupled to the pole 30, and an arm 50 may connect the articulated connector 40 and the elevating module 60.

Accordingly, the head 10 may be supported by the motion module MM, the pole 30, and the base 20, and may be spaced upward from the ground.

Referring to FIGS. 2 and 3 , the head 10 may include a display panel 11, a middle cabinet 12, a frame 13, an end frame 14, and a back cover 15.

The display panel 11 may form a front surface of the head 10. For example, the display panel 11 may be an OLED panel, an LCD panel, or an LED panel. The display panel 11 may divide an image into a plurality of pixels and may output the image while controlling color, brightness, and chroma of the respective pixels. The display panel 11 may be divided into an active area, in which the image is displayed, and a de-active area in which the image is not displayed. The display panel 11 may generate light corresponding to red, green, or blue color in response to a control signal.

The middle cabinet 12 may extend along a periphery of the display panel 11. A horizontal part 12H may be disposed at the front of the display panel 11. A vertical part 12V may intersect the horizontal part 12H and may cover the side of the display panel 11. For example, the middle cabinet 12 may include a metal or plastic material. The middle cabinet 12 may be referred to as a side frame or a guide panel.

The frame 13 may be disposed at the rear of the display panel 11. Electronic components, such as a Printed Circuit Board (PCB), may be coupled to a rear surface of the frame 13. For example, the frame 13 may include a metal material. The frame 13 may be referred to as a mount plate or a module cover.

The end frame 14 may form a periphery of the head 10. A horizontal part 14H may be disposed at the front of the horizontal part 12H of the middle cabinet 12. The vertical part 14V may cover the side of the vertical part 12V of the middle cabinet 12. For example, the end frame 14 may include a metal or plastic material.

The back cover 15 may form a rear surface of the head 10. The back cover 15 may cover the rear of the frame 13 and may be coupled to the frame 13.

Referring to FIGS. 3 and 4 , a backlight unit 110 may be disposed between the display panel 11 and the frame 13 and may be coupled to the frame 13. In this case, the display panel 11 may be referred to as an LCD panel. The backlight unit 110 may include an optical layer 111 and an optical sheet 112. The optical layer 111 may include a substrate 111 a, at least one light source 111 b, a reflective sheet 111 c, and a diffusion plate 111 d.

The substrate 111 a may be coupled to a front surface of the frame 13. The substrate 111 a may have a plate shape or may be formed in the shape of a plurality of straps which are vertically spaced apart from each other. The at least one light source 111 b may be mounted on the substrate 111 a. For example, the light source 111 b may include alight emitting diode (LED). An electrode pattern for connecting the light source 111 b to an adapter may be formed on the substrate 111 a. The reflective sheet 111 c may be disposed at the front of the substrate 111 a. The reflective sheet 111 c may have a hole 111 h in which the light source 111 b is disposed. The diffusion plate 111 d may be disposed at the front of the reflective sheet 111 c. A spacer 111 s may support a rear surface of the diffusion plate 111 d at a position between the reflective sheet 111 c and the diffusion plate 111 d.

The optical sheet 112 may be disposed at the front of the diffusion plate 111 d. A rear surface of the optical sheet 112 may come into close contact with the diffusion plate 111 d, and a front surface of the optical sheet 112 may come into close contact with or may be adjacent to the rear surface of the display panel 11. The optical sheet 112 may include at least either a diffusion sheet or a prism sheet. A coupling part 112 d may be formed on at least one edge of the optical sheet 112.

Accordingly, light from the light source 111 b may be provided to the display panel 11 via the diffusion plate 111 d and the optical sheet 112. The display panel 11 of the present disclosure may be an OLED panel requiring no backlight unit 110 described above or may be another type of panel.

Referring to FIGS. 3 and 5 , a backlight unit 110′ may be disposed between the display panel 11 and the frame 13 and may be coupled to the frame 13. In this case, the display panel 11 may be referred to as an LCD panel. The backlight unit 110′ may include an optical layer 111′ and an optical sheet 112. The optical sheet 111′ may include a substrate 111 a′, at least one light source 111 b′, a reflective sheet 111 f, and a light guide plate 111 e. The light guide plate 111 e may be disposed between the frame 13 and the optical sheet 112 and may be supported by the frame 13.

The substrate 111 a′ may be adjacent to a periphery of the light guide plate 111 e and may be coupled to the frame 13. The at least one light source 111 b′ may be mounted on the substrate 111 a′. For example, the light source 111 b′ may include a light emitting diode (LED). An electrode pattern for connecting the light source 111 b′ to an adapter may be formed on the substrate 111 a′. The reflective sheet 1 l 1 f may be disposed between the frame 13 and the light guide plate 111 e and may be supported by the frame 13.

Accordingly, light from the light source 111 b′ may be provided to the display panel 11 via the diffusion plate 111 e and the optical sheet 112. The display panel 11 of the present disclosure may be an OLED panel requiring no backlight unit 110′ described above or may be another type of panel.

Referring to FIG. 6 , electronic components may be mounted on the rear surface of the frame 13 and may include a plurality of boards PSU, MB, and TC and speakers SPKa and SPKb.

A power supply board PSU may be disposed closer to the first short side SS1 than to the second short side SS2 and may be coupled to the rear surface of the frame 13. The power supply board PSU may supply power to the respective components of the display device. For example, the power supply board PSU may supply power to the light sources 111 b and 111 b′ of the backlight units 110 and 110′ (see FIGS. 4 and 5 ). The power supply board PSU may be referred to as an LED driver.

The main board MB may be disposed closer to the second short side SS2 than to the first short side SS1 and may be coupled to the rear surface of the frame 13. The main board MB may control the display device.

The timing controller board TC may be disposed below the power supply board PSU and the main board MB and may be coupled to the rear surface of the frame 13. The timing controller board TC may be electrically connected to the display panel 11 (see FIG. 3 ) through a cable (not shown) and may provide an image signal to the display panel 11.

The speakers SPKa and SPKb may be disposed above the plurality of boards PSU, MB, and TC and may be coupled to the rear surface of the frame 13. For example, a left speaker SPKa may be disposed closer to the first short side SS1 than to the second short side SS2 and may direct sound in a lateral direction. For example, a right speaker SPKb may be disposed closer to the second short side SS2 than to the first short side SS1 And may laterally direct sound.

A locking unit 18 may be coupled to the rear surface of the frame 13. The locking unit 18 may be disposed below the center of the frame 13.

Referring to FIG. 7 , the back cover 15 may cover the rear of the frame 13 and may be coupled to the frame 13. Positions of speaker holes 15 a and 15 b formed in the back cover 15 may correspond to positions of the speakers SPKa and SPKb (see FIG. 6 ) mounted to the frame 13.

Fixing parts 13H may protrude rearward from the rear surface of the frame 13. The fixing parts 13H may be PEM nuts. The fixing parts 13H and the locking unit 18 may be exposed to the outside through a hole 15 h formed at the center of the back cover 15.

Referring to FIGS. 7 and 8 , a fixing plate 41 may have a circular plate shape corresponding to the hole 15 h of the back cover 15.

Fixing holes 41H may be formed in the fixing plate 41 and may be aligned with the fixing parts 13H. A fastening member (not shown), such as a screw, may be fastened to the fixing parts 13H through the fixing holes 41H. Accordingly, the fixing plate 41 may be coupled to the frame 13.

Referring to FIGS. 8 and 9 , a front bracket 42 of the articulated connector 40 may be disposed at the rear of the fixing plate 41 and may have a generally plate shape. A pair of top protrusions 42 a 1 and 42 a 2 may protrude upward from an upper side of the front bracket 42 and may be spaced apart from each other in the left-right direction. A pair of bottom protrusions 42 b 1 and 42 b 2 may protrude downward from a lower side of the front bracket 42 and may be spaced apart from each other in the left-right direction. The pair of bottom protrusions 42 b 1 and 42 b 2 may be engaged with a pair of engaging portions 1831 a and 1831 b of the locking unit 18 passing through the fixing plate 41, and the pair of top protrusions 42 al and 42 a 2 may be inserted and coupled to a pair of holes formed in an upper portion of the fixing plate 41. Accordingly, the front bracket 42 may be removably coupled to the fixing plate 41.

A pivot shaft 44 may extend in the front-rear direction. A diameter of a head 44 a of the pivot shaft 44 may be greater than a diameter of a body 44 b. A pair of cut-outs 44 c may be formed in a lateral surface of the body 44 b and may face each other. The front bracket 42 may have a hole 42 h which is formed at the center thereof, and through which the body 44 b may pass. The hole 42 h of the front bracket 42 may have the same shape as a shape of a longitudinal section of the body 44 b. Accordingly, the pivot shaft 44 and the front bracket 42 may rotate together in an axial direction.

A front grab 45 a may be disposed between the head 44 a and a front surface of the front bracket 42. A hole 45 ah of the front grab 45 a may be aligned with the hole 42 h of the front bracket 42 and may have the same shape as the hole 42 h. The body 44 b may pass through the holes 45 ah and 42 h. The front grab 45 a may be fixed to the front bracket 42. That is, the front grab 45 a may rotate together with the pivot shaft 44 and the front bracket 42.

Referring to FIGS. 10 and 11 , a rear bracket 43 may be disposed at the rear of the front bracket 42. The rear bracket 43 may include a mount 43F, a left wing 43L, and a right wing 43R.

The mount 43F may face the front bracket 42 and may have a circular mount hole 43Fh. At least one washer 43Fw may be disposed between the front bracket 42 and the mount 43F and may have a circular hole. The body 44 d of the pivot shaft 44 may pass through the hole of the washer 43Fw and the mount hole 43Fh and may rotate independently of the washer 43Fw and the mount 43F.

The left wing 43L may extend rearward from a left side of the mount 43F. The right wing 43R may extend rearward from a right side of the mount 43F. A plurality of members 45 c: 45 c 1, 45 c 2, 45 c 3, 45 c 4, and 45 c 5, which will be described below, may be coupled to the mount 43F at positions between the left wing 43L and the right wing 43R.

A rear grab 45 c 1 may be disposed opposite the washer 43Fw with respect to the mount 43F and may have a circular hole 45 ch through which the body 44 b of the pivot shaft 44 passes. The rear grab 45 c 1 may be fixed to a rear surface of the mount 43F.

Further, a plurality of fixing holes 45 ca and a plurality of slots 45 cb may be formed in the rear grab 45 c 1 and may be spaced apart from each other in a circumferential direction of the rear grab 45 c 1. The plurality of fixing holes 45 ca and the plurality of slots 45 cb may be arranged alternately in a circumferential direction of the rear grab 45 c 1. For example, the fixing holes 45 ca or the slots 45 cb may be spaced apart from each other at 90-degree intervals. A length of the slot 45 cb may be greater than a length of the fixing hole 45 ca in the circumferential direction of the rear grab 45 c 1.

A disc 45 c 2 may be disposed at the rear of the rear grab 45 c 1 and may have a hole 45 c 2 h through which the body 44 b passes and which has the same shape as the longitudinal section of the body 44 b. A plurality of bosses 45 cc may protrude from a front surface of the disc 45 c 2 toward the rear grab 45 c 1 and may be spaced apart from each other in a circumferential direction of the disc 45 c 2. For example, the bosses 45 cc may be spaced apart from each other at 90-degree intervals. A size of the boss 45 cc may be equal to a size of the fixing hole 45 ca or may correspond thereto. That is, when the boss 45 cc is inserted into the fixing hole 45 ca, rotation of the disc 45 c 2 and the pivot shaft 44 may be limited to some degree by the rear grab 45 c 1. In addition, when the boss 45 cc is inserted into the slot 45 cb, the disc 45 c 2 and the pivot shaft 44 may rotate within a trajectory of the slot 45 cb.

The washer 45 c 3 may be disposed at the rear of the disc 45 c 2 and may have a circular hole (not numbered) through which the body 44 b of the pivot shaft 44 passes.

A disc spring 45 c 4 may be disposed opposite the disc 45 c 2 with respect to the washer 45 c 3 and may have a circular hole (not numbered) through which the body 44 b of the pivot shaft 44 passes. The disc spring 45 c 4 may have elasticity and may be convex forward or rearward. The disc spring 45 c 4 may generate an elastic force in the axial direction.

A cap 45 c 5 may be disposed at the rear of the disc spring 45 c 4 and may have a hole 45 c 5 h through which the body 44 b of the pivot shaft 44 passes. The hole 45 c 5 h may have the same shape as a shape of the longitudinal section of the body 44 b. The cap 45 c 5 may be fixed to an end of the body 44 b.

Accordingly, the pivot shaft 44 may rotate together with the front bracket 42, the front grab 45 a, the disc 45 c 2, and the cap 45 c 5. In addition, the pivot shaft 45 may rotate independently of the washer 43Fw, the rear bracket 43, the rear grab 45 c 1, the washer 45 c 3, and the disc spring 45 c 4. In other words, even when the pivot shaft 45 rotates, the washer 43Fw, the rear bracket 43, the rear grab 45 c 1, the washer 45 c 3, and the disc spring 45 c 4 may not rotate.

Further, a user may pivot the head 10 (see FIG. 8 ), fixed to the front bracket 42, about the pivot shaft 44. For example, the head 10 may pivot within a range of +90 degrees to −90 degrees. Also, unless an external force at a certain level or higher is applied, the elastic force of the disc spring 45 c 41 and 45 c 2 may allow the head 10 to be maintained at a constant pivot angle. In addition, during a pivot motion of the head 10, the user may feel the sense of coupling when the boss 45 cc is inserted into the fixing hole 45 ca or the slot 45 cb. That is, when the boss 45 cc moves out of the slot 45 to be inserted into the fixing hole 45 ca, the user may feel that the head 10 is positioned at a pivot angle of zero degrees or +90 or −90 degrees.

Referring to FIG. 12 , a holder 47 may be disposed between the left wing 43L and the right wing 43R. A holder body 470 may cover the rear of the mount 43F of the rear bracket 43. A first part 47L may protrude toward the mount 43F from a left part of the holder body 470 and may be adjacent to the left wing 43L. A second part 47R (see FIG. 10 ) may protrude toward the mount 43F from a right part of the holder body 47 and may be adjacent to the right wing 43R.

A tilt shaft 46 may extend in the left-right direction. The tilt shaft 46 may pass through the left wing 43L, the first part 47L, the second part 47R, and the right wing 43R. A head (not numbered), which is a first end of the tilt shaft 46, may be seated on a side surface of the left wing 43L. A screw thread may be formed at a second end of the tilt shaft 46, and a fastening member 46 d, such as a nut, may be fastened to the second end of the tilt shaft 46 on the right wing 43R.

In addition, the tilt shaft 46 may have a generally cylindrical shape and may be fixed to the left wing 43L and the right wing 43R. The tilt shaft 46 may be rotatably coupled to the holder 47. That is, the tilt shaft 46 may provide a tilt axis. At least one washer 46 v may be disposed between the second part 47R and the right wing 43R and may have a circular hole through which the tilt shaft 46 passes.

An elastic member 46 a may be disposed between the left wing 43L and the right wing 43R. The elastic member 46 a may be wound a plurality of times around an outer circumference of the tilt shaft 46 and may have elasticity. The elastic member 46 a may be a coil-shaped spring.

Further, a portion 46 b of the elastic member 46 a may extend in a direction intersecting the tilt shaft 46 without being wound around the tilt shaft 46. The portion 46 b of the elastic member 46 a may be stopped by a seating part 43 h which protrudes rearward from the mount 43F.

In addition, a first end of the elastic member 46 a may be formed on the portion 46 b, and a second end of the elastic member 46 a may be fixed to the inside of the holder 47. A disc spring 46 w may be adjacent to a second end 46 c of the elastic member 46 a and may be disposed between the elastic member 46 a and the second part 47R. The disc spring 46 w may have a circular hole (not numbered) through which the tilt shaft 46 passes. The disc spring 46 w may be convex toward the elastic member 46 a and may generate an elastic force in an axial direction of the tilt shaft 46.

Accordingly, the tilt shaft 46 may rotate together with the rear bracket 43, the front bracket 42, and the plurality of members 45 c 5, 45 c 4, 45 c 3, 45 c 2, 45 c 1, 43Fw, 45 a, and 44. In response to the rotation of the tilt shaft 46, the head 10 (see FIG. 8 ) fixed to the front bracket 42 may be tilted upward or downward. For example, the head 10 may be tilted within a range of +25 degrees to −25 degrees. In addition, unless an external force at a certain level or higher is applied, the elastic force of the elastic member 46 a and the disc spring 46 w may allow the head 10 to be maintained at a constant tilt angle.

Referring to FIGS. 13 and 14 , a first rotation unit 48 may be disposed at the rear of the holder 47. A first connecting part 471 may connect the holder 47 and the first rotation unit 48. For example, the holder 47, the first connecting part 471, and the first rotation unit 48 may be formed as one body.

A cable reel 49 may be disposed at the rear the front bracket 42. The cable reel 49 may be coupled to the left wing 43L and the right wing 43R via a fastening member 49F such as a screw.

The rear bracket 43 and the holder 47 may be disposed in an inner space of a hollow cylinder-shaped reel body (not shown) of the cable reel 49. A first plate 49 a and a second plate 49 b of the cable reel 49 may protrude from a front end and a rear end, respectively, of the reel body in a radial direction of the reel body and may extend along an outer circumference of the reel body. That is, each of the first plate 49 a and the second plate 49 b may have a generally ring shape. Accordingly, a cable C may be wound around the reel body of the cable reel 49 at a position between the first plate 49 and the second plate 49 b.

Referring to FIGS. 14 and 15 , the front bracket 42 may be removably coupled to the fixing plate 41 (see FIG. 8 ).

An inner cover 40 cl may cover the rear of the cable reel 49 and may have a cover hole 40 h through which the first rotation unit 48 passes. Fastening members 49 f 1 and 49 f 2 may pass through the cable reel 49 to protrude rearward and may be coupled to the inside of the inner cover 40 c 1. For example, the fastening members 49 f 1 and 49 f 2 may be screws or bolts.

An inner circumference of an outer cover 40 c 2 may be coupled to an outer circumference of the inner cover 40 c 1. The inner cover 40 cl and the outer cover 40 c 2 may cover the rear of the hole 15 h of the back cover 15.

Referring to FIGS. 16 and 17 , the arm 50 may include arm bodies 51 and 52. An upper arm body 51 and a lower arm body 52 may be coupled to each other. The arm 50 may be referred to as a rod 50 or a link 50.

A front portion of the upper arm body 51 may be spaced upward from a front portion of the lower arm body 52. A front groove 50 g 1 may be formed in the front portions of the arm bodies 51 and 52 and may have a “U” shape that is open forwardly. A rear portion of the upper arm body 51 may be spaced upward from a rear portion of the lower arm body 52. A rear groove 50 g 2 may be formed in the rear portions of the arm bodies 51 and 52 and may have a “U” shape that is open rearwardly.

An upper insertion hole 51 a may be formed by vertically passing through the front portion of the upper arm body 51 and may face the front groove 50 g 1. An upper fastening hole 51 b may be formed by vertically passing through the rear portion of the upper arm body 51 and may face the rear groove 50 g 2.

A lower fastening hole 52 a may be formed by vertically passing through the front portion of the lower arm body 52 and may be aligned with the upper insertion hole 51 a. A lower insertion hole 52 b may be formed by vertically passing through the rear portion of the lower arm body 52 and may be aligned with the upper fastening hole 51 b.

A cable groove 50 c may be formed in a lower surface of the lower arm body 52 and may extend in a longitudinal direction of the lower arm body 52. The cable C (see FIG. 14 ) may be placed in the cable groove 50 c.

Referring to FIG. 18 , an upper cover 53 may cover a surface of the upper arm body 51 (see FIG. 17 ). A lower cover 54 may cover a surface of the lower arm body 52 (see FIG. 17 ). The upper cover 53 and the lower cover 54 may be separately formed or may be formed as one body.

The first rotation unit 48 may be inserted into the front groove 50 g 1 and may be rotatably coupled to the arm 50. A second rotation unit 68 may be inserted into the rear groove 50 g 2 and may be rotatably coupled to the arm 50. The second rotation unit 68 may protrude toward the rear groove 50 g 2 from a vertical member 61 which will be described later.

Referring to FIGS. 18 and 19 , the first rotation unit 48 may include a first body 480, a first fastening member 48 a, a first upper lock washer 48 b, a first disc spring 48 d, a first upper washer 48 e, a first upper bushing 48 f, a first lower bushing 48 g, a first lower washer 48 h, and a first lower lock washer 48 c. The first rotation unit 48 may be referred to as a first swivel unit 48 or a first swivel module 48.

The first body 480 may be open at the top and bottom. The first body 480 may have a substantially donut shape. For example, the first body 480 may be formed as one body with the first connecting part 471. The first body 480 may be inserted into the front groove 50 g 1.

The first fastening member 48 a may extend vertically. The first fastening member 48 a may be inserted into the arm 50 through the upper insertion hole 51 a (see FIG. 17 ) and may pass through a hole 480 h formed at the center of the first body 480. A head 48 ah of the first fastening member 48 a may be disposed inside the upper arm body 51. The first fastening member 48 a may be screwed into the lower fastening hole 52 a (see FIG. 17 ).

The first upper lock washer 48 b may be disposed under the head 48 ah of the first fastening member 48 a, and the first fastening member 48 a may pass through the first upper lock washer 48 b. The first upper lock washer 48 may be a toothed lock washer, and a tooth 48 bt of the first upper lock washer 48 b may be inserted and fixed into a groove (not numbered) formed on the inside of the upper arm body 51.

The first disc spring 48 d may be disposed under the first upper lock washer 48 b. The first disc spring 48 d may be convex toward the first upper lock washer 48 b and may generate an elastic force in an axial direction of the first fastening member 48 a.

The first upper washer 48 e may be disposed under the first disc spring 48 d, and the first fastening member 48 a may pass through the first upper washer 48 e.

The first upper bushing 48 f may be disposed opposite the first disc spring 48 d with respect to the first upper washer 48 e. The first fastening member 48 a may pass through the first upper bushing 48 f. The first upper busing 48 f may have a cylindrical shape having a flange (not numbered) formed at an upper end thereof. The flange of the first upper bushing 48 f may contact the first upper groove 480 a formed along the periphery of the hole 480 h on an upper surface of the first body 480. A portion (not numbered) of the first upper bushing 48 f may be inserted into the hole 480 h of the first body 480 and may be disposed between an inner circumferential surface of the first body 480 and an outer circumferential surface of the first fastening member 48 a.

The first lower bushing 48 g may be disposed opposite the first upper busing 48 f and may be spaced downward from the first upper bushing 48 f. The first fastening member 48 a may pass through the first lower bushing 48 g. The first lower bushing 48 g may have a cylindrical shape having a flange (not numbered) formed at a lower end thereof. The flange of the first lower bushing 48 g may contact the first lower groove 480 b formed along the periphery of the hole 480 h on a lower surface of the first body 480. A portion (not numbered) of the first lower bushing 48 g may be inserted into the hole 480 h of the first body 480 and may be disposed between the inner circumferential surface of the first body 480 and the outer circumferential surface of the first fastening member 48 a.

The first lower washer 48 h may be disposed under the first lower bushing 48 g, and the first fastening member 48 a may pass through the first lower washer 48 h.

The first lower lock washer 48 c may be disposed opposite the first lower bushing 48 g with respect to the first lower washer 48 h, and the first fastening member 48 a may pass through the first lower lock washer 48 h. The first lower lock washer 48 c may be a toothed lock washer, and a tooth 48 ct of the first lower lock washer 48 c may be inserted and fixed into a groove (not numbered) formed on the inside of the lower arm body 52.

Accordingly, the first body 480 may rotate with respect to the first fastening member 48 a. That is, the first fastening member 48 a may provide a first swivel axis. In addition, unless an external force at a certain level or higher is applied, the elastic force of the first disc spring 48 d may allow the head 10 to be maintained at a constant swivel angle.

Referring to FIGS. 18 and 20 , the second rotation unit 68 may include a second body 680, a second fastening member 68 a, a second lower lock washer 68 b, a second disc spring 68 d, a second lower washer 68 e, a second lower bushing 68 f, a second upper bushing 68 g, a second upper washer 68 h, and a second upper lock washer 68 c. The second rotation unit 68 may be referred to as a second swivel unit 68 or a second swivel module 68.

The second body 680 may be open at the top and bottom. The second body 680 may have a substantially donut shape. For example, the second body 680 may be connected to the vertical member 61 by a second connecting part 611. For example, the second body 680, the second connecting part 611, and the vertical member 61 may be formed as one body. The second body 680 may be inserted into the rear groove 50 g 2.

The second fastening member 68 a may extend vertically. The second fastening member 68 a may be inserted into the arm 50 through the lower insertion hole 52 b (see FIG. 17 ) and may pass through a hole 680 h formed at the center of the second body 680. A head 68 ah of the second fastening member 68 a may be disposed inside the lower arm body 52. The second fastening member 68 a may be screwed into the upper fastening hole 51 b (see FIG. 17 ).

The second lower lock washer 68 b may be disposed above the head 68 ah of the second fastening member 68 a, and the second fastening member 68 a may pass through the second lower lock washer 68 b. The second lower lock washer 68 b may be a toothed lock washer, and a tooth 68 bt of the second lower lock washer 68 b may be inserted and fixed into a groove (not numbered) formed on the inside of the lower arm body 52.

The second disc spring 68 d may be disposed above the second lower lock washer 68 b. The second disc spring 68 d may be convex toward the second lower lock washer 68 b and may generate an elastic force in an axial direction of the second fastening member 68 a.

The second lower washer 68 e may be disposed above the second disc spring 68 d, and the second fastening member 68 a may pass through the second lower washer 68 e.

The second lower bushing 68 f may be disposed opposite the second disc spring 68 d with respect to the second lower washer 68 e. The second fastening member 68 a may pass through the second lower bushing 68 f The second lower bushing 68 f may have a cylindrical shape having a flange (not numbered) formed at a lower end thereof. The flange of the second lower bushing 68 f may contact the second lower groove 680 a formed along the periphery of the hole 680 h on a lower surface of the second body 680. A portion (not numbered) of the second lower bushing 68 f may be inserted into the hole 680 h of the second body 680 and may be disposed between an inner circumferential surface of the second body 680 and an outer circumferential surface of the second fastening member 68 a.

The second upper bushing 68 g may face the second lower busing 68 f and may be spaced upward from the second lower busing 68 f. The second fastening member 68 a may pass through the second upper busing 68 g. The second upper busing 68 g may have a cylindrical shape having a flange (not numbered) formed at an upper end thereof. The flange of the second upper busing 68 g may contact the second upper groove 680 b formed along the periphery of the hole 680 h on an upper surface of the second body 680. A portion (not numbered) of the second upper bushing 68 g may be inserted into the hole 680 h of the second body 680 and may be disposed between the inner circumferential surface of the second body 680 and the outer circumferential surface of the second fastening member 68 a.

The second upper washer 68 h may be disposed above the second upper bushing 68 g, and the second fastening member 68 a may pass through the second upper washer 68 h.

The second upper lock washer 68 c may be disposed opposite the second upper bushing 68 g with respect to the second upper washer 68 h, and the second fastening member 68 a may pass through the second upper lock washer 68 c. The second upper lock washer 68 c may be a toothed lock washer, and a tooth 68 ct of the second upper lock washer 68 c may be inserted and fixed into a groove (not numbered) formed on the inside of the upper arm body 51.

Accordingly, the second body 680 may rotate with respect to the second fastening member 68 a. That is, the second fastening member 68 a may provide a second swivel axis. In addition, unless an external force at a certain level or higher is applied, the elastic force of the second disc spring 68 d may allow the head 10 to be maintained at a constant swivel angle.

Referring to FIG. 21 , the arm 50 may extend in a direction intersecting the head 10 and the pole 30. The arm 50 may connect the articulated connector 40 and the elevating module 60. The second rotation unit 68 of the elevating module 60 may be connected with the vertical member 61 by the second connecting part 611. The second connecting part 611 may pass through the pole 30.

The vertical member 61 may extend in a longitudinal direction of the pole 30. The vertical member 61 may be accommodated inside the pole 30.

The pole 30 may extend vertically and may surround the vertical member 61. A plurality of ribs 30 a, 30 b, 30 c, and 30 d may protrude toward the vertical member 61 from an inner circumferential surface of the pole 30 and may be spaced apart from each other in a circumferential direction of the pole 30. A first rib 30 a, a second rib 30 b, a third rib 30 c, and a fourth rib 30 d may be located at the vertices of an arbitrary square inside the pole 30.

In addition, an insertion part 31 of the pole 30 may be inserted into and coupled to a port 21 formed in an upper surface of the base 20.

Referring to FIGS. 21 and 22 , the vertical member 61 may be generally in the shape of a cylinder cut in half. The vertical member 61 may be open at the rear and bottom, and the top of the vertical member 61 may be blocked by a partition wall 61 w.

A stem 63 s may extend vertically and may be aligned with the vertical member 61. A lower end of the stem 63 s may be inserted into the port 21 of the base 20.

Gas springs 62 and 63 may include an upper shaft 62 and a lower shaft 63 coupled to the upper shaft 62. The upper shaft 62 may extend in a longitudinal direction of the vertical member 61. The upper shaft 62 may have a cylindrical shape with a closed top. At least a portion of the upper shaft 62 may be accommodated in the vertical member 61. The lower shaft 63 may extend in a longitudinal direction of the upper shaft 62 and may have a smaller diameter than that of the upper shaft 62. That is, the lower shaft 63 may be inserted into the upper shaft 62. A lower end of the lower shaft 63 may be fixed on the stem 63 s.

Clamps 64 and 65 may be disposed opposite the vertical member 61 with respect to the upper shaft 62. In other words, the upper shaft 62 may be disposed between the vertical member 61 and the clamps 64 and 65. For example, the clamps 64 and 65 may include a plurality of clamps 64 and 65 which are vertically spaced apart from each other.

The clamps 64 and 65 may include semi-cylinders 640 and 650, left flanges 641 and 651, and right flanges 642 and 652. The semi-cylinders 640 and 650 may contact an outer circumference of the upper shaft 62. The left flanges 641 and 651 may extend leftward from a first side of the semi-cylinders 640 and 650 and may be coupled to first parts 61 s 1 and 65 s 1 of the vertical member 61 by fastening members 64F and 65F. The right flanges 642 and 652 may extend rightward from a second side of the semi-cylinders 640 and 650 and may be coupled to a second part (not shown) of the vertical member 61 by a fastening member (not shown).

Accordingly, the upper shaft 62 may be removably coupled to the vertical member 61 and may move upward or downward along the lower shaft 63.

Referring to FIGS. 22 and 23 , rollers 66 a, 66 b, 67 a, and 67 b may be adjacent to the clamps 64 and 65. For example, first rollers 66 a and 66 b may be adjacent to a first clamp 64, and second rollers 67 a and 67 b may be adjacent to a second clamp 65.

The first rollers 66 a and 66 b may include a first left roller 66 a and a first right roller 66 b. A body 66 a 1 a of a first left pin 66 a 1 may pass through the first left roller 66 a and a left part 61L of the vertical member 61. A flange 66 a 1 b of the first left pin 66 a 1 may be disposed between the first left roller 66 a and the left part 61L. The first left roller 66 a may be coupled to the left part 61L by the first left pin 66 a 1. A body 66 b 1 a of a first right pin 66 b 1 may pass through the first right roller 66 b and a right part 61R of the vertical member 61. A flange 66 b 1 b of the first right pin 66 b 1 may be disposed between the first right roller 66 b and the right part 61R. The first right roller 66 b may be coupled to the right part 61R by the first right pin 66 b 1.

For example, the second rollers 67 a and 67 b may have the same shape as the first rollers 66 a and 66 b. That is, the above description of the first rollers 66 a and 66 b may also be applied to the second rollers 67 a and 67 b. Accordingly, the second left roller 67 a may be coupled to the left part 61L, and the second right roller 67 b may be coupled to the right part 61R.

In addition, the left rollers 66 a and 67 a may be disposed between the third rib 30 c and the fourth rib 30 d and may contact the third rib 30 c and the fourth rib 30 d. The right rollers 66 b and 67 b may be disposed between the first rib 30 a and the second rib 30 b and may contact the first rib 30 a and the second rib 30 b.

Accordingly, the vertical member 61 may smoothly move up and down inside the pole 30 by the rollers 66 a, 66 b, 67 a, and 67 b.

Referring to FIGS. 22 and 24 , a left flange 641 of the first clamp 64 may be disposed between the third rib 30 c and the fourth rib 30 d. A first right flange 642 of the first clamp 64 may be disposed between the first rib 30 a and the second rib 30 b. The first clamp 64 may include a first central protrusion 64 a, a first left protrusion 64 b, and a first right protrusion 64 c.

The first central protrusion 64 a may protrude toward the inside of the pole 30 from a first semi-cylinder 650 and may contact the inside of the pole 30. The first left protrusion 64 b may protrude toward the third rib 30 c from the first left flange 641 and may contact the third rib 30 c. The first right protrusion 64 c may protrude toward the second rib 30 b from the first right flange 642 and may contact the second rib 30 b. Accordingly, the first central protrusion 64 a, the first left protrusion 64 b, and the first right protrusion 64 c may cause friction between the vertical member 61 and the pole 30.

For example, the second clamp 65 may be spaced downward from the first clamp 64 and may have the same shape as the first clamp 64. That is, the above description of the first clamp 64 may also be applied to the second clamp 65. Accordingly, a second central protrusion 65 a, a second left protrusion 65 b, and a second right protrusion 65 c of the second clamp 65 may cause friction between the vertical member 61 and the pole 30.

Accordingly, unless an external force at a certain level or higher is applied, the frictional force between the protrusions 64 a, 64 b, 64 c, 65 a, 65 b, and 65 c and the pole 30 may allow the vertical member 61 to be maintained at a constant position (height) with respect to the base 20.

Referring to FIGS. 23 and 24 , a cable groove 61 g may be formed in a front portion 61F of the vertical member 61 and may be elongated vertically. The cable C may be inserted into the cable groove 61 g. The cable C may be disposed along the cable groove 50 c (see FIG. 14 ) of the arm 50 and may be electrically connected to the head 10. The cable C may be disposed along the stem 63 s (see FIG. 22 ) and may be electrically connected to a battery Bt (see FIG. 1 ) disposed in the base 20 and the like. The battery Bt may supply power to the head 10 through the cable C. The battery Bt may be a rechargeable battery. The cable C may be a power cable and/or a signal cable. The cable C may have several strands.

Referring to FIGS. 25 and 26 , the base 20 may include a lower body 20 a and an upper body 20 b. The lower body 20 a may form a lower surface of the base 20 and may have a generally round tray shape which is open at the top. The upper body 20 b may form an upper surface of the base 20 and may have a generally round tray shape which is open at the bottom. An outer diameter D20 of the upper body 20 b may be substantially equal to an outer diameter of the lower body 20 a.

A flat weight 81 may be disposed in an inner space of the base 20, i.e., a space between the lower body 20 a and the upper body 20 b, and may be disposed on the lower body 20 a. The flat weight 81 may be referred to as a support weight or a flat plate.

A weight 82 may be disposed in the inner space of the base 20 and may be disposed on the flat weight 81. The weight 82 may be referred to as a core weight.

A substate BC and a bottom connector 89 may be disposed in the inner space of the base 20 and may be disposed on the flat weight 81. An indicator ID may be disposed on the weight 82. The battery Bt and a wheel assembly 29 may be coupled to a lower surface of the lower body 20 a.

Referring to FIGS. 27 and 28 , a seating part 24 may be formed by being pressed upward from the lower surface of the lower body 20 a. The seating part 24 may protrude upward beyond an upper surface of the lower body 20 a. An opening 24 h may be formed in a side wall of the seating part 24 and may communicate with the inner space of the base 20.

The battery Bt may be inserted into the seating part 24 from below the lower body 20 a. The battery Bt may be seated on and coupled to the seating part 24. A second cable C11 may be electrically connected to the battery Bt and may pass through the opening 24 h. A battery cover 20 c may be removably coupled to the lower body 20 a by a fastening member Fyy such as a screw, and may cover a lower surface of the battery Bt. The cover 20 c may form the lower surface of the base 20 along with the lower body 20 a.

For example, the battery Bt may be a rechargeable battery. For example, the battery Bt may be replaceable.

A recessed portion 22 may be formed by being pressed upward from the lower surface of the lower body 20 a. The recessed portion 22 may protrude upward beyond the upper surface of the lower body 20 a. The recessed portion 22 may have a cylindrical shape. The recessed portion 22 may be adjacent to a circumference of the lower body 20 a. For example, a plurality of recessed portions 221, 222, 223, 224, and 225 may be spaced apart from each other along the circumference of the lower body 20 a.

A lower fixing hole 22 a may be formed through an upper surface of the recessed portion 22. For example, the lower fixing hole 22 a may include a pair of fixing holes 22 a which are spaced apart from each other. A base hole 22 b may be formed through the upper surface of the recessed portion 22 and may be spaced apart from the lower fixing hole 22 a. For example, the base hole 22 b may be disposed between the pair of fixing holes 22 a. Each of the plurality of recessed portions 221, 222, 223, 224, and 225 may have the lower fixing hole 22 a and the base hole 22 b.

The flat weight 81 may be formed flat. The flat weight 81 may be parallel to the upper surface of the lower body 20 a. The flat weight 81 may have a generally circular plate shape. The flat weight 81 may include a flat weight hole 81 h, a mounting surface 81 m, and major arcs 811, 812, 813, 814, and 815 (see FIG. 25 ).

The flat weight hole 81 h may be formed by passing through the flat weight 81 in a thickness direction of the flat weight 81 and may correspond to the seating part 24. When the flat weight 81 is seated on the lower body 20 a, the seating part 24 may pass through the flat weight hole 81 h.

The mounting surface 81 m may be adjacent to the flat weight hole 81 h and may form a portion of the upper surface of the flat weight 81.

The major arcs 811, 812, 813, 814, and 815 may be formed from a circumference of the flat weight 81 toward the inside of the flat weight 81. The major arcs 811, 812, 813, 814, and 815 may be holes formed by cutting out a portion of the flat weight 81 and may be in the shape of an arc greater than a semi-circle. When the flat weight 81 is seated on the lower body 20 a, the recessed portion 22 may be disposed in the major arcs 811, 812, 813, 814, and 815. Each of a first major arc 811, a second major arc 812, a third major arc 813, a fourth major arc 814, and a fifth major arc 815 may extend along a portion of a lateral surface of each of a first recessed portion 221, a second recessed portion 222, a third recessed portion 223, a fourth recessed portion 224, and a fifth recessed portion 225. Each of the first major arc 811, the second major arc 812, the third major arc 813, the fourth major arc 814, and the fifth major arc 815 may be engaged with the lateral surface of each of the first recessed portion 221, the second recessed portion 222, the third recessed portion 223, the fourth recessed portion 224, and the fifth recessed portion 225.

A fastening member Fy, such as a screw, may pass through the lower surface of the lower body 20 a and may be coupled to the flat weight 81 seated on the lower body 20 a. For example, a plurality of fastening members Fy may be adjacent to an outer circumference of the flat weight 81 and may be spaced apart from each other along the circumference of the flat weight 81. Accordingly, the flat weight 81 may be removably coupled to the lower body 20 a.

The substrate BC may be mounted on the mounting surface 81 m. The substrate BC may be a Printed Circuit Board (PCB). The substrate BC may be referred to as a battery charger. A bottom plate BCP may be disposed between the substrate BC and the mounting surface 81 m.

The bottom connector 89 may be disposed on the flat weight 81. For example, the bottom connector 89 may be disposed between the first recessed portion 221 and the second recessed portion 222. The bottom connector 89 may include a bottom housing 89 a, at least one pin 89 b, and a coupling hole 89 h. The bottom housing 89 a may have a hollow cylindrical shape, and the pin 89 b may be disposed in an inner space of the bottom housing 89 a. The coupling hole 89 h may be disposed outside of the bottom housing 89 a. The bottom connector 89 may be referred to as a bottom docking connector.

A first end of a first cable C10 may be electrically connected to the bottom connector 89, and a second end of the first cable C10 may be electrically connected to a first terminal T11 of the substrate BC. A first end of the second cable C11 may be electrically connected to a second terminal T12 of the substrate BC, and a second end of the second cable C11 may be electrically connected to the battery Bt.

A coupling part 81P may protrude upward from the upper surface of the flat weight 81. A plurality of coupling parts 81P may be disposed around the bottom connector 89.

Referring to FIGS. 28 and 29 , a weight 82 may be adjacent to the circumference of the flat weight 81 and may be seated on the flat weight 81. For example, a plurality of weights 821, 822, 823, and 824 may be disposed along the circumference of the flat weight 81 and may be adjacent to each other. Alternatively, the plurality of weights 821, 822, 823, and 824 may be formed as one body.

A first weight 821 may extend along a front portion of a lateral wall of the lower body 20 a. The first recessed portion 221 and the second recessed portion 222 may be received in a groove formed in a lower surface of the first weight 821. A fastening member Fx, such as a screw, may pass through the first weight 821 and may be coupled to a portion of the flat weight 81 on which the first weight 821 is placed. That is, the first weight 821 may be coupled to the flat weight 81. Meanwhile, the first cable C10 may be disposed in a cable groove formed in a lower surface of the first weight 821.

The second weight 822 may extend along a left portion of the lateral wall of the lower body 20 a. The third recessed portion 223 may be received in a groove formed in a lower surface of the second weight 822. The fastening member Fx, such as a screw, may pass through the second weight 822 and may be coupled to a portion of the flat weight 81 on which the second weight 822 is placed. That is, the second weight 822 may be coupled to the flat weight 81.

The third weight 823 may extend along a rear portion of the lateral wall of the lower body 20 a. The fourth recessed portion 224 may be received in a groove formed in a lower surface of the third weight 823. The fastening member Fx, such as a screw, may pass through the third weight 823 and may be coupled to a portion of the flat weight 81 on which the third weight 823 is placed. That is, the third weight 823 may be coupled to the flat weight 81.

The fourth weight 824 may extend along a right portion of the lateral wall of the lower body 20 a. The fifth recessed portion 225 may be received in a groove formed in a lower surface of the fourth weight 824. The fastening member Fx, such as a screw, may pass through the fourth weight 824 and may be coupled to a portion of the flat weight 81 on which the fourth weight 824 is placed. That is, the fourth weight 824 may be coupled to the flat weight 81.

In addition, an upper fixing hole 82 h 1 may be formed in each of the plurality of weights 821, 822, 823, and 824, and may be aligned with the lower fixing hole 22 a of each of the plurality of recessed portions 221, 222, 223, 224, and 225.

In this case, the first recessed portion 221 and the second recessed portion 222 may be coupled to the first weight 821 in such a manner that a fastening member F1 (see FIG. 32 ), such as a screw, is coupled to the upper fixing hole 82 h 1 of the first weight 821 through the lower fixing hole 22 a. In the same manner, the third recessed portion 223, the fourth recessed portion 224, and the fifth recessed portion 225 may be coupled to the second weight 822, the third weight 823, and the fourth weight 824, respectively.

Accordingly, the plurality of weights 821, 822, 823, and 824 may be coupled to the flat weight 81 and the lower body 20 a.

The aforementioned plurality of weights 821, 822, 823, and 824 may be disposed along the circumference of the lower body 20 a. The weights 821, 822, 823, and 824 may include a metal material. For example, the weights 821, 822, 823, and 824 may be formed by casting using a material such as Fe. In this case, the weights 821, 822, 823, and 824 may improve stability of the base 20. Here, as the stability of the base 20 increases, the base 20 placed on the ground may not be easily overturned.

The aforementioned flat weight 81 may support the plurality of weights 821, 822, 823, and 824. Flatness of the plurality of weights 821, 822, 823, and 824 may be corrected by the flat weight 81. For example, the flat weight 81 may be formed by die casting using a material such as aluminum Al. A mass of the flat weight 81 may be smaller than a mass of the weight 82. A thickness of the flat weight 81 may be smaller than a thickness of the weight 82. In this case, the stability of the base 20 may be mainly achieved by the weight 82, and the flatness of the weight 82 may be corrected by the flat weight 81.

The bottom housing 89 a of the bottom connector 89 may pass through the first weight 821. A fastening member 89F (see FIG. 38 ), such as a screw, may pass through a hole (see FIG. 38 ) of the first weight 821 disposed around the bottom housing 89 a and may be coupled to the coupling hole 89 h of the bottom connector 89. Accordingly, the bottom connector 89 may be coupled to the first weight 821 at a position between the flat weight 81 and the first weight 821.

A ridge 82 a may be formed at the center of the first weight 821 and may be in the shape of a monticule. The ridge 82 a may be formed around the bottom housing 89 a of the bottom connector 89. The ridge 82 a may correspond to a shape of the port 21 (see FIG. 26 ) of the upper body 20 b and may support the port 21.

A supporter 81S may protrude upward from an upper surface of the flat weight 81 and may be adjacent to the substrate BC. For example, the supporter 81S may be provided in plurality. At a position near the substrate BC, the supporter 81S may support the upper body 20 b and may prevent damage to the substrate BC caused due to sagging or pressing of the upper body 20 b.

Referring to FIG. 30 , the lower body 20 a may include a bottom 20 al and a lateral wall 20 a 2. A snap groove 20 aq may be formed in the lateral wall 20 a 2 of the lower body 20 a. The upper body 20 b may include a top 20 b 1 and a lateral wall 20 b 2. A snap projection 20 bp may be formed on the inside of the lateral wall 20 b 2 of the upper body 20 b and may be coupled to the snap groove 20 aq by a snap-fit connection. Accordingly, the upper body 20 b may be removably coupled to the lower body 20 a.

A support rib 20 r may be formed on the inside of the lateral wall 20 a 2 of the lower body 20 a. The support rib 20 r may be adjacent to or may contact a lateral surface of the weight 82 and/or the flat weight 81. Accordingly, the support rib 20 r may minimize deformation of the base 20.

Referring back to FIGS. 28 and 29 , a weight hole 82 h 2 may be formed in each of the plurality of weights 821, 822, 823, and 824. For example, the number of the weight holes 82 h 2 may be four or any number. Four weight holes 82 h 2 may be located at the vertices of a square.

The weight holes 82 h 2 of the first weight 821 may vertically communicate with the base holes 22 b of the first recessed portion 221 and the second recessed portion 222. The weight hole 82 h 2 of the second weight 822 may vertically communicate with the base hole 22 b of the third recessed portion 223. The weight hole 82 h 2 of the third weight 823 may vertically communicate with the base hole 22 b of the fourth recessed portion 224. The weight hole 82 h 2 of the fourth weight 824 may vertically communicate with the base hole 22 b of the fifth recessed portion 225.

Referring to FIGS. 31 and 32 , the wheel assembly 29 may include an upper plate 29 a, a lower plate 29 b, a bearing 29 c, a shaft 29 d, a bridge 29 e, and a wheel 29 f.

The upper plate 29 a may be disposed in the base hole 22 b (see FIG. 28 ) of the recessed portion 22. The upper plate 29 a may contact a groove of the weight 82 in which the recessed portion 22 is received. A fastening member F2, such as a screw, may pass through the upper plate 29 a and the base hole 22 b and may be coupled to the weight hole 82 h 2 (see FIG. 29 ). Accordingly, the upper plate 29 a may be coupled to the weight 82. The lower plate 29 b may be disposed below the upper plate 29 a. A shaft 29 d may pass through the lower plate 29 b and the upper plate 29 a and may couple the lower plate 29 b to the upper plate 29 a. The lower plate 29 b may rotate about an axial direction of the shaft 29 d. The shaft 29 d may provide a first axis of rotation of the wheel assembly 29 which is vertically parallel. The bearing 29 c may be disposed between the lower plate 29 b and the upper plate 29 a. For example, the bearing 29 c may be a plurality of ball bearings disposed around a circumference of the shaft 29 d.

The bridge 29 e may extend downward from the lower plate 29 b. For example, the bridge 29 e may be formed as one body with the lower plate 29 b.

The wheel 29 f may be rotatably coupled to the bridge 29 e and may be coupled to the lower plate 29 b via the bridge 29 e. The wheel 29 f may provide a second axis of rotation of the wheel assembly 29 which is horizontally parallel. A center of rotation 29 fc of the wheel 29 f may be offset by a certain distance e10 from the axial direction of the shaft 29 d. A movement trajectory of the wheel 29 f, which corresponds to the rotation of the lower plate 29 b, may be formed on the inside of the recessed portion 22.

Further, the wheel 29 f may protrude downward beyond the bottom 20 al of the lower body 20 a. That is, the wheel 29 f may be placed on the ground, and the bottom 20 al may be spaced upward from the ground. For example, the wheel 20 f may include rubber, silicon, resin, or ABS material.

For example, the wheel assembly 29 may include a plurality of wheel assemblies 291, 292, 293, 294, and 295 which are spaced apart from each other along the circumference of the lower body 20 a.

A first wheel assembly 291 may be coupled to the first weight 821 (see FIG. 29 ) through the base hole 22 b (see FIG. 28 ) of the first recessed portion 221. A second wheel assembly 292 may be coupled to the first weight 821 (see FIG. 29 ) through the base hole 22 b (see FIG. 28 ) of the second recessed portion 222. A third wheel assembly 293 may be coupled to the second weight 822 (see FIG. 29 ) through the base hole 22 b (see FIG. 28 ) of the third recessed portion 223. A fourth wheel assembly 294 may be coupled to the third weight 823 (see FIG. 29 ) through the base hole 22 b (see FIG. 28 ) of the fourth recessed portion 224. A fifth wheel assembly 295 may be coupled to the fourth weight 824 (see FIG. 29 ) through the base hole 22 b (see FIG. 28 ) of the fifth recessed portion 225.

Accordingly, as the plurality of wheel assemblies 291, 292, 293, 294, and 295 are coupled to the plurality of weights 821, 822, 823, and 824 having flatness corrected by the flat weight 81 (see FIG. 29 ), the plurality of wheel assemblies 291, 292, 293, 294, and 295 may have improved balance and driving stability.

Meanwhile, a bottom hole 20 h may be formed by passing through the lower body 20 a in a thickness direction of the lower body 20 a and may be adjacent to the circumference of the lower body 20 a. A position of the bottom hole 20 h may correspond to a position of the pole 30 (see FIG. 33 ) coupled to the base 20.

In this case, the first wheel assembly 291 and the second wheel assembly 292 may be adjacent to the bottom hole 20 h. With respect to a center 0 c of the base 20, an angle theta a between the first wheel assembly 291 and the second wheel assembly 292 may be a minimum angle among angles between the plurality of wheel assemblies 291, 292, 293, 294, and 295. With respect to the center 0 c of the base 20, each of an angle theta b between the second wheel assembly 292 and the third wheel assembly 293, an angle theta c between the third wheel assembly 293 and the fourth wheel assembly 294, an angle theta d between the fourth wheel assembly 294 and the fifth wheel assembly 295, and an angle theta e between the fifth wheel assembly 295 and the first wheel assembly 291 may be greater than the angle theta a. For example, the angles theta a, theta b, theta c, theta d, and theta e may be substantially equal to each other.

Accordingly, two or more wheel assemblies, such as the first and second wheel assemblies 291 and 292, may be coupled to the pole 30 (see FIG. 33 ), thereby stably supporting a portion of the base 20 on which load is concentrated.

Referring to FIGS. 33 to 35 , the port 21 may be formed in the upper body 20 b and may be in the shape of a monticule. A first guide rib 21 r may be formed on the inside of the port 21. A second guide rib 82 r may be formed on a lateral wall of the ridge 82 a. For example, the second guide rib 82 r may be defined by grooves formed by cutting out a portion of the lateral wall of the ridge 82 a. The second guide rib 82 r may be vertically aligned with the first guide rib 21 r.

An insertion part 31 may be formed at a lower end of the pole 30. The insertion part 31 may be part of the pole 30. An outer diameter of the insertion part 31 may be smaller than an outer diameter of the pole 30 (see tz of FIG. 35 ) and may be substantially equal to an inner diameter of the port 21. A guide slit 31 s may be formed in a lateral surface of the insertion part 31 and may be vertically aligned with the first guide rib 21 r. When the insertion part 31 is inserted into the port 21, the first guide rib 21 r and the second guide rib 82 r may be inserted into the guide slit 31 s. The insertion part 31, inserted into the port 21, may be surrounded by the ridge 82 a and may be seated on a seating surface 82 b of the first weight 821.

A fastening member F, such as a screw, may pass through the bottom hole 20 h, the coupling part 81P (see FIG. 28 ), and a hole (see FIG. 38 ) aligned with the coupling part 81P of the first weight 821 and may be coupled to a plurality of ribs 30 a, 30 b, 30 c, and 30 d of the pole 30. Accordingly, the pole 30 may be coupled to the port 21.

The stem 63 s may be partially disposed within the insertion part 31 and may be coupled to the insertion part 31 by a fastening member Fz such as a screw.

A top connector 79 may be disposed inside the insertion part 31 and may be coupled to the stem 63 s by a fastening member 79F such as a screw. The top connector 79 may face downward. The top connector 79 may be referred to as a top docking connector.

A bottom connector 89 may face upward through the port 21. The bottom connector 89 may be vertically aligned with the top connector 79. The bottom connector 89 may be referred to as a bottom docking connector.

Referring to FIGS. 36 to 38 , the top connector 79 may include a top housing 79 a, at least one pin hole 79 b, and a bracket 790. The top housing 79 a may have a cylindrical shape, and the pin hole 79 b may be formed inside the top housing 79 a. The bracket 790 may be coupled to an upper surface of the top housing 79 a and may have an insertion groove 790 u formed along a circumference of the top housing 79 a. The bracket 790 may have a hole 790 h through which the fastening member 79F (see FIG. 35 ) may pass. A top groove 79 c may be formed in a lateral surface of the top housing 79 a and may extend vertically. A top boss 79 d may protrude toward the insertion groove 790 u from a portion of the bracket 790 that defines a boundary of the insertion groove 790 u.

The bottom connector 79 may include the bottom housing 89 a, the at least one pin 89 b, and a jack 89 j. The bottom housing 89 a may have a hollow cylindrical shape, and the pin 89 b may be disposed in the inner space of the bottom housing 89 a. For example, the number of the pins 89 b may be five or any number. The jack 89 i may be formed on one side of the bottom connector 89. The bottom boss 89 c may be formed on the inside of the bottom housing 89 a. The bottom groove 89 d may be formed in an outer surface of the bottom housing 89 a and may face the bottom boss 89 c.

Accordingly, when insertion part 31 of the pole 30 is inserted into the port 21, the bottom boss 89 c may be inserted into the top groove 79 c, and the top boss 79 d may be inserted into the bottom groove 89 d. In addition, the pin 89 b may be inserted into the pin hole 79 b. In this case, the cable C connected to the top connector 79 and the first cable C10 connected to the bottom connector 89 may be electrically connected to each other through the pin hole 79 b and the pin 89 b.

A power cable (not shown) may be electrically connected to the jack 89 i. In this case, external power may be supplied to the battery Bt through the power cable, the bottom connector 89, the first cable C10, the first terminal T11, the substrate BC, the second terminal T12, and the second cable C11, thereby charging the battery Bt (see FIG. 29 and the like).

The power cable may be removed from the jack 89 i. In this case, the power of the battery Bt may be supplied to the head 10 through the second cable C11, the second terminal T12, the substrate BC, the first terminal T11, the first cable C10, the bottom connector 89, the top connector 79, and the cable C.

The indicator ID may be electrically connected to a third terminal T13 of the substrate BC through the third cable C12 and may detect a remaining capacity of the battery Bt. A light emitting element IDL (see FIG. 33 ) of the indicator ID may be formed on the upper body 20 b and may display a remaining capacity of the Battery Bt for a user.

Referring to FIG. 39 , the head 10 may be spaced upward from the base 20. A user may pivot the head 10. A pivot axis may pass through the center of the head 10 and may be orthogonal to the head 10. Referring to the left drawing of FIG. 39 , the head 10 may be positioned in a horizontal mode. Referring to the right drawing of FIG. 39 , the head 10 may be positioned in a vertical mode.

Referring to FIG. 40 , a user may tilt the head 10. A tilt axis is located behind the center of the head 10 and may be a horizontal axis parallel to the head 10. The user may swivel the head 10. A first swivel axis may be a vertical axis adjacent to a first end of the arm 50. A second swivel axis may be a vertical axis adjacent to a second end of the arm 50. The user may raise or lower the head 10 along the pole 30.

The pivot, tilt, swivel, and elevating motions of the head 10 described above may be performed independently of each other. For example, the head 10 may pivot within a range of +90 degrees to −90 degrees. For example, the head 10 may be tilted within a range of +25 degrees to −25 degrees. For example, the head 10 may swivel within a range of +65 degrees to −65 degrees. For example, in the horizontal mode, the head 10 may be located at a position of 1065 mm to 1265 mm above the base 20 or the ground.

Referring to FIGS. 39 and 40 , the base 20 may stably support various motions of the display device by using the motion module MM. In addition, the base 20 may improve stability of movement of the display device by using the wheel assembly 29 (see FIG. 34 ).

Referring to FIGS. 1 to 40 , a display device according to an embodiment of the present disclosure may include: a head including a display panel; an arm to which the head is pivotally coupled; a pole to which the arm is coupled; and a base to which the pole is coupled, wherein the base includes: a lower body forming a bottom; an upper body which is coupled to the lower body and to which the pole is fixed; a weight disposed between the lower body and the upper body; and a wheel disposed outside of the lower body, passing through the lower body and coupled to the weight.

The pole may be adjacent to an edge of the upper body, and the wheel may include a plurality of wheels coupled to the weight, wherein the plurality of wheels may include: a first wheel adjacent to a position corresponding to the pole of the lower body; and a second wheel opposite to the first wheel with respect to the position corresponding to the pole of the lower body, wherein with respect to a center of the lower body, an angle between the first wheel and the second wheel may be a minimum angle among angles between the plurality of wheels.

The base may further include a flat weight which is disposed between the lower body and the weight and to which the weight is coupled, wherein the wheel may pass through the lower body and the flat weight and is coupled to the weight.

The flat weight may be formed flat, and a mass of the weight may be greater than a mass of the flat weight.

The lower body may be directly coupled to the flat weight and the weight, and the weight may be directly coupled to the flat weight.

The flat weight may have a circular plate shape, and the weight may include a plurality of weights disposed along an edge of the flat weight.

The lower body may further include a recessed portion formed from the lower body toward the upper body, the recessed portion having a base hole facing the weight, wherein the flat weight may further include major arcs formed at an edge of the flat weight and extending along a portion of a lateral surface of the recessed portion, wherein the wheel may be coupled to the weight through the base hole.

The lower body may further include recessed portions formed from the lower body toward the upper body and accommodating a portion of the wheel, wherein the wheel may include a first axis of rotation intersecting the lower body and passing through the recessed portion; and a second axis of rotation parallel to the lower body and offset by a certain distance from the first axis of rotation.

The display device may further include a wheel assembly having the wheel, wherein the wheel assembly may include: an upper plate fixed to the weight; a lower plate opposite to the upper plate; a shaft which passes through the lower plate and the upper plate and to which the lower plate is coupled so as to be rotatable about the second axis of rotation; a bearing disposed between the upper plate and the lower plate; and a bridge which extends from the lower plate toward the wheel and to which the wheel is coupled so as to be rotatable about the second axis of rotation.

The lower body may include a lateral wall forming a perimeter of the lower body; and a support rib formed at an inside of the lateral wall, wherein the weight may be adjacent to the lateral wall, and the support rib may be adjacent to or may contact a lateral surface of the weight.

The upper body may be coupled to the lower body by a snap-fit connection, and the upper body and the lower body may include a plastic material.

The upper body may further include a port through which the pole is inserted and which is seated on the weight, wherein the weight may further include: a ridge formed at an upper surface of the weight and surrounding the pole inserted into the port; and a fastening member passing through the lower body and the weight and coupled to the pole.

The pole may include an insertion part inserted into the port, the insertion part having a slit formed at a lateral surface of the insertion part, wherein the port may further include a first guide rib formed at an inside of the port and inserted into the slit, and the ridge may further include a second guide rib formed at a lateral surface of the ridge and inserted into the slit.

The display device may further include: a top connector disposed inside the pole; and a bottom connector disposed on the weight, coupled to the top connector, and electrically connected to the top connector.

The display device may further include a battery disposed between the lower body and the upper body, coupled to the lower body, and electrically connected to the bottom connector.

The display device according to the present disclosure has the following effects.

According to at least one of the embodiments of the present disclosure, a display device including a stand for a display panel may be provided.

According to at least one of the embodiments of the present disclosure, a structure for freely adjusting an angle or position of a head having a display panel may be provided.

According to at least one of the embodiments of the present disclosure, a structure for allowing various motions of a head, including a pivot motion, a tilt motion, a swivel motion, and an elevating motion, to be performed independently of each other may be provided.

According to at least one of the embodiments of the present disclosure, a structure for improving standing stability of a display device may be provided.

According to at least one of the embodiments of the present disclosure, a structure for improving driving stability of a moving base having a wheel may be provided.

Certain embodiments or other embodiments of the invention described above are not mutually exclusive or distinct from each other. Any or all elements of the embodiments of the invention described above may be combined or combined with each other in configuration or function.

For example, a configuration “A” described in one embodiment of the invention and the drawings and a configuration “B” described in another embodiment of the invention and the drawings may be combined with each other. Namely, although the combination between the configurations is not directly described, the combination is possible except in the case where it is described that the combination is impossible.

The foregoing embodiments are merely examples and are not to be considered as limiting the present disclosure. The scope of the present disclosure should be determined by rational interpretation of the appended claims, and all modifications within the equivalents of the disclosure are intended to be included within the scope of the present disclosure. 

What is claimed is:
 1. A display device comprising: a head including a display panel; an arm to which the head is pivotally coupled; a pole to which the arm is coupled; and a base to which the pole is coupled, wherein the base comprises: a lower body forming a bottom and comprising a plurality of upwardly recessed portions configured to accommodate a plurality of wheel assemblies disposed below the lower body; an upper body which is coupled to the lower body; a first plate disposed between the lower body and the upper body; a second plate disposed between the first plate and the lower body; a battery; and a battery control board configured to control charging of the battery, wherein the second plate comprises a plurality of inwardly formed arc portions corresponding to the plurality of upwardly recessed portions of the lower body, and wherein the second plate comprises a main inwardly formed arc portion corresponding to a position at which the pole is coupled to the base.
 2. The display device of claim 1, wherein the first plate is configured to provide a weight to the base.
 3. The display device of claim 1, wherein the first plate comprises a recessed groove configured to accommodate passage therethrough of a wire for delivering power for powering the display panel.
 4. The display device of claim 1, wherein the battery and the battery control board are positioned opposite to each other with respect to a line intersecting a position at which the pole is connected to the base.
 5. The display device of claim 1, wherein the plurality of wheel assemblies are secured to the first plate through the lower body.
 6. The display device of claim 5, wherein the plurality of wheel assemblies comprise a first wheel assembly and a second wheel assembly positioned opposite each other with respect to a position where the pole is coupled to the base, and wherein the first wheel assembly and the second wheel assembly are positioned closer to each other than any other pair of wheel assemblies of the plurality of wheel assemblies.
 7. The display device of claim 6, wherein securing members for the plurality of wheel assemblies pass through the lower body and the second plate to be coupled to the first plate.
 8. The display device of claim 1, wherein the second plate comprises a recess corresponding to a position at which the first plate and the second plate are coupled together.
 9. The display device of claim 5, wherein a weight of the first plate is greater than a weight of the second plate.
 10. The display device of claim 1, wherein the lower body further comprises: a lateral wall forming a perimeter of the lower body; and a support rib formed at an inside of the lateral wall, wherein the first plate is adjacent to the lateral wall, and the support rib is adjacent to or contacts a lateral surface of the first plate.
 11. The display device of claim 10, wherein the upper body is coupled to the lower body by a snap-fit connection, and the upper body and the lower body comprises a plastic material.
 12. The display device of claim 1, wherein the upper body further comprises a port through which the pole is inserted, wherein the first plate further comprises a support portion configured to support the pole inserted into the port; and wherein a fastening member extends through the lower body and the first plate to be coupled to the pole to secure the pole to the base.
 13. The display device of claim 12, further comprising: a top connector disposed inside the pole; and a bottom connector disposed at the support portion and configured to be electrically coupled to the top connector when the pole is inserted into the port. 